A BOY IS HANGING FROM A BRANCH OF A TREE THE TENSION IN THEW ARMS WILL BE MAXIMUM WHEN THE ANGLE BETWEEN THE ARMS IS

120degrees

This does not make sense to me. As the angle between the arms gets greater, tension is increased.

To determine the angle between the arms when the tension is maximum, we need to consider the forces acting on the boy.

When a boy hangs from a branch of a tree, his weight acts vertically downward. The forces in the boy's arms must counteract his weight to maintain static equilibrium (no net force and zero acceleration).

Let's assume the weight of the boy is W and the angle between the arms is θ. When the angle between the arms is 90 degrees (θ = 90°), the forces in the arms are fully vertical, opposing the weight of the boy.

As the angle θ decreases, the vertical component of the forces in the arms decreases, while the horizontal component increases. The horizontal component does not contribute to supporting the weight, so the tension in the arms decreases.

On the other hand, when the angle θ increases beyond 90 degrees, the vertical component of the forces in the arms starts decreasing, and the horizontal component starts increasing in the opposite direction. This causes the tension in the arms to decrease further.

Therefore, the tension in the arms will be maximum when the angle between the arms is 90 degrees (θ = 90°).